SACRAMENTO — California Atty. Gen. Xavier Becerra has emerged as a leading national figure in what Democrats call their “resistance” to the Trump administration, filing a flurry of 38 lawsuits against the federal government in just the last year and a half.

The state’s legal challenges have attacked federal actions on issues including immigration, the environment, the U.S. census, education, the internet, the rights of transgender people, and healthcare.

California’s lawsuits claim Trump administration actions conflict with existing federal law, are overreaching of executive authority, fail to follow procedures for public input on rule changes or are based on whim without proper rationale.

So far, Becerra has won 12 key court rulings in the lawsuits he filed and lost on three. In other cases, the federal government reversed the policy challenged in lawsuits before a court could decide. Most of the legal cases are still awaiting a final determination by the courts.

Here’s a rundown of the 38 legal actions filed by the state attorney general.

Immigration

California is home to an estimated quarter of the 11.1 million immigrants in the country illegally. Becerra, who describes himself as the “proud son of immigrants,” has targeted many of his lawsuits — nine so far — to challenge Trump’s get-tough policy on immigration enforcement

Becerra sued over Trump’s proposal to build a wall at the U.S.-Mexico border, alleging it failed to comply with federal and state environmental laws, but a judge ruled against the state. More recently, Becerra went to court to challenge the federal policy of separating immigrants who enter the country illegally from their children, claiming it violates the due process rights of parents. That case is pending, although courts have ruled in other cases that children must be reunited with parents.

California also led a lawsuit against the Trump administration’s decision to end a program that protects immigrants brought to the country illegally as children from deportation. The lawsuit argued that canceling the program violates the Constitution, and the courts issued a preliminary injunction.

One of Becerra’s first lawsuits was over a Trump administration travel ban on immigrants from six countries with predominantly Muslim populations, claiming that the order represented unconstitutional religious discrimination. Judges in other cases put a freeze on the order. When Trump issued a revised travel ban, Becerra joined other states in suing again.

The Supreme Court last month upheld Trump’s latest version of travel restrictions.

Becerra has also gone to court to oppose the Trump administration’s attempt to place immigration enforcement conditions on certain public safety grants for law enforcement in cities that adopted so-called sanctuary laws that restrict cooperation with immigration agents. A request for a preliminary injunction was denied.

Other pending lawsuits sought to compel federal agencies to provide documents showing the rationale behind decisions to put conditions on grants to sanctuary cities, and to toughen enforcement of immigration laws.

When the administration proposed adding a question on citizenship to the 2020 U.S. census, Beccerra sued, claiming that the action was “arbitrary and capricious” and lacking proper rationale.

Healthcare

With three lawsuits, California led the effort to combat efforts by the Trump administration and others to roll back provisions of the Patient Protection and Affordable Care Act, known popularly as Obamacare.

Becerra won a preliminary injunction to block federal rules that allowed employers to deny women cost-free birth control that the state argued was guaranteed under the Affordable Care Act.

The state was not successful in suing the administration over its stopping cost-sharing reduction payments that states argued are required by the Affordable Care Act. A judge denied a request for an emergency injunction, but the state is seeking a summary judgment on the merits of its claims.

Becerra also led a coalition of 16 attorneys general in winning a court decision allowing them to be part of the opposition to an application by Texas and other states that are seeking to halt operation of the

Affordable Care Act nationwide.

Education

As the first person in his family to graduate from college, Becerra has said education is an important issue for him, and he has filed a trio of lawsuits to press his case. He sued the U.S. Department of Education challenging its decision to refrain from helping students obtain forgiveness of their loans in cases where they went to universities that engaged in fraud.

California filed a lawsuit against the Education Department claiming that it had failed to process debt-relief claims submitted by students who took out federal loans to attend for-profit colleges. In addition, Becerra went to court to ask that federal officials require for-profit schools to meet a standard of preparing students for “gainful employment in a recognized occupation.”

Environment

With California leading the move from coal and oil to cleaner energy sources, it is no surprise that the most lawsuits filed by the attorney general — 21 so far — have challenged Trump administration proposals to roll back environmental protections.

In May, Becerra led a coalition of 17 states in suing the U.S. Environmental Protection Agency claiming that it had violated the federal Clean Air Act in rolling back a requirement that cars average nearly 55 miles per gallon by 2025. The case is still pending.

Last week, Becerra led a coalition of 16 states in suing the EPA to challenge its suspension of a mandate that most rebuilt diesel engines installed in heavy-duty trucks meet the same emissions standards applied to new engines.

California previously sued the EPA for delaying other rules aimed at reducing air pollution, winning a case that said the agency improperly failed to identify parts of the country that have not achieved smog-reduction goals. The state also won an injunction after the agency balked at regulating methane created by oil and gas operations on public lands.

Becerra is still awaiting a judgment on a lawsuit that challenged the administration over the repeal of restrictions on hydraulic fracturing oil extraction, known as fracking, on federal lands. A decision also has not been made yet on a state lawsuit that argued the EPA violated the Clean Air Act by repealing a requirement that major sources of air pollutants, including petroleum refineries, install equipment to minimize pollution.

The state also sued twice over delay in a federal rule requiring companies that extract oil, gas and coal to pay royalties to states. A judge has ruled in favor of the state’s claim in one of the cases.

Becerra also went to court with other states to force the EPA to reverse its suspension of safeguards for agricultural workers, claiming that if workers are not given training and education on pesticides, they risk being harmed. The EPA later backed down and implemented the training.

The agency also reversed course when it was hit with a California lawsuit claiming that it had improperly delayed enforcement of an energy-efficiency standard for ceiling fans, and a court sided with Becerra in a lawsuit alleging the federal government had failed to enact energy standards for portable air conditioners and walk-in freezers.

Last month, Becerra sued the EPA, claiming that it had acted improperly in allowing companies to manufacture products with hydrofluorocarbons — a refrigerant that is a potent greenhouse gas. The case is pending.

Another legal challenge was filed against the EPA over its suspension of the 2015 Clean Water Rule aimed at protecting lakes and streams from pollutants. The court has not yet ruled in that case.

Before EPA Administrator Scott Pruitt resigned this month amid scandal, Becerra sued to force the release of documents the state believed would shed light on Pruitt’s suspected conflicts of interest.

And when the U.S. Department of the Interior proposed to restart federal leases for coal mining, California sued and is awaiting a ruling.

California and other states went to court and won a challenge to the decision by the National Highway Traffic Safety Administration to delay increased penalties for automakers whose vehicles fail to comply with fuel-efficiency standards.

LGBTQ rights,

net neutrality

Becerra joined transgender service members in suing to challenge Trump’s ban on transgender people serving in the military. A preliminary injunction was granted that could affect a subsequent executive order limiting service.

He also took the Federal Communications Commission to court, challenging its action to repeal net-neutrality rules,arguing its action was overreach. The case is pending.

patrick.mcgreevy@latimes.com

Twitter: @mcgreevy99